Herbal recipe to treat malaria earns Nobel Prize

China's Youyou Tu received helping hand from a 3rd century healer in developing new drug.

Part of the ancient recipe as recorded by 3rd century herbalist Ge Hong that led to a new drug to fight malaria.
(Photo: Youyou Tu/Nature)

Youyou Tu of China’s Academy of Traditional Chinese Medicine has been announced as one of three scientists to win this year's Nobel Prize in Medicine. The 84-year-old medical scientist and pharmaceutical chemist is being recognized for her discovery of artemisinin, a drug that has saved countless lives in the fight against the mosquito-borne disease malaria.

Unlike other discoveries first made in a laboratory, Tu instead turned to ancient notes left behind by past generations for clues on how best to potentially fight malaria. During the late '60s, she and her team scoured thousands of recipes of Chinese traditional herbs, compiling 640 examples that might have some antimalarial activity.

Sweet wormwood, native to Asia, contains a compound that has proven extremely effective in the fight against malaria. (Photo: Kristian Peters/WikiMedia Commons)

The most promising herbal extract was from Artemisia annua L. (Qinghao), a type of sweet wormwood native to Asia. According to a paper published in 2011, the herb was shown to inhibit parasite growth by as much as 68 percent. Those results, however, were inconsistent — a problem Tu theorized likely had something to do with the way the scientists were extracting the active ingredient.

The breakthrough came when Tu spotted a recipe by a third century healer from the Jin Dynasty named Ge Hong. Instead of using high-temperature extraction as the researchers were doing in the lab, Hong's method was to take a bunch of sweet wormwood, soak it in cold water, and then wring it out to obtain the necessary drug. This simple alternative resulted in a much higher concentration of artemisinin.

The ancient handbook (A) and the instructions (B) that led to Youyou Tu's discovery of a new way to fight malaria. (Photo: Youyou Tu/Nature)

"We were certain that we had found an entirely new chemical structure," Tu said in 2011. "Of course, that was one of the happiest moments of my career as a researcher. I was really excited to have eventually found it, because the rest of the world was unable to find the solution. We found it in traditional Chinese medicine, herbal medicine. This was an exciting moment."

Treatments containing derivatives of artemisinin are still widely used today as a first line of defense against malaria infections.

Tu shares this year's award with Ireland's William Campbell and Japan's Satoshi Omura, who studied soil bacteria to isolate a compound known as avermectin. Their discovery has since led to drugs that have nearly eradicated debilitating diseases such as river blindness and elephantiasis.

Speaking with Reuters, Omura said the credit should not go to him, but more the bacteria that created the chemical in the first place.

"I really wonder if I deserve this," he said. "I have done all my work depending on microbes and learning from them, so I think the microbes might almost deserve it more than I do."